Compressor lubrication supply mechanism



May-31,1949. c. B- FITES COMPRESSOR LUBRICATION SUPPLY MECHANISM ,WWWIIII/IIIIIIIII/Z M/J FIG. 5.

FIG. 3.

INVENTORZ CYRIL B. FITES BY Can L9 fl AT TORNEY.

Patented May 31 1 949 UNITED STATES PATENT OFFICE COMPRESSOR LUBRICATION SUPPLY MECHANISM tion of Delaware Application August 20, 1947, Serial No. 769,685

This invention relates to compressor lubricating means and in its more specific aspects is directed to a mechanism for replenishing the oil supply for an engine driven air compressor from the crankcase of the driving engine or other source of supply.

The object of this invention is to provide means for periodically replenishing the oil in the oil reservoir for an air compressor by means of a device mounted on the compressor casing to which oil is supplied from the crankcase of the automotive engine which drives the compressor or from any, other oil source, the device being operated by pressure changes occurring in the compressor oil reservoir.

In the drawings:

Figure 1 shows a sectional schematic view of a portion of an air compressor with the lubricating device attached,

Figure 2 shows an enlarged sectional view of the lubricating device in a different position from that shown in Figure 1,

Figure 3 discloses a partial elevational sectional view of a modified form of the lubricating device,

Figure 4 discloses an enlarged view of the lubricating device and check valve shown in Figure 3, and

Figure 5 is a sectional view taken along the line 55 of Figure 4.

Referring now to Figure 1 of the drawings, numeral 6 designates the casing for the reservoir of an air compressor provided with a shaft I on which an air pump (not shown) is rotatably mounted. Compressed air passes from the air pump through conduit 8 into oil separator 9, into the reservoir in casing 6, into cooling member ID and thence through conduit l2, past check valve l3 through the exhaust port in fitting l4, into conduit I5 and tank I6. Conduits I1 and I8 control an inlet valve and an unloading valve, respectively, (both not shown) so that the reservoir in casingfi may be subjected to variations in pressure responsive to tank l6 pressures as is customary in air compressor operation.

The oil reservoir formed in casing 6 contains an oil supply l9 and when this supply is subjected to pressure, oil is forced through duct 20 and the connecting passageways in shaft 1 to the moving 9 Claims. (Cl. 230-206) 2323' reciprocably mounted in a cylinder bore in the housing. A valve seat 24 is secured to the piston 23 and is engageable with a suitable valve seat 23' formed in housing 22. A spring 26 is inserted in the bore in piston 23' and in a bore in cylinder closure 25 and holds the pistons in the position illustrated in Figure 2 when the compressor is operating under no-load or not delivering pressure fluid to the reservoir in casing 6. The casing 22 is provided with a pair of ports 27 and 28 into which conduits 29 and 30, respectively, are connected. The other end of the conduit 30 is preferably connected to the lower side of vessel 3| so that oil will flow by gravity into pump chamber 34 While the other end of conduit 29 extends into the top of vessel 3|. Vessel 3| is vented to atmosphere so that the oil therein and in injector chamber 34 is at atmospheric pressure.

During the pumping operation of the air compressor, the unloading valve closes the outlet of conduit l8 and the space above the oil level 36 in casing 6 is filled with compressed air and the lubricant I9 is subject to the same pressure as tank [6. The pressure of the compressed air causes pistons 23-23 to move to the right, compressing spring 26 and seating valve 24 onvalve seat 24' to prevent the escape of pressure fluid through chamber 34. As soon as the pressure requirements of tank iii are satisfied, the compressor inlet valve is closed and the unloading valve opens the outlet of conduit [8, relieving the space above the lubricant I9 in casing 6 to atmosphere. Spring 26 now moves pistons 2323 to the left until collar 33 engages the cooperating stop in housing 22.

The oil to be delivered into the reservoir of casing 3 occupies the space provided by a slot 35' in the connecting member 35. This slot is filled with oil and as the pistons 23-23' move to the left by the action of spring 26 to the position in Figure 2, the oil is delivered to the oil reservoir in casing 6 provided the oil level 36 is not above the uppermost part of slot 35. The collar 33 on piston 23' limits the leftward movement of pistons 23-23 in the bore and prevents direct flow of oil from chamber 34 into the reservoir of casing 6.

A modified form of the invention is illustrated in Figures 3, 4, and 5 in which an injector housing 3'! is associated with casing 6. Housing 31 has a cylindrical bore therein in which pistons 38-38 are slidable axially. .Piston members 3ll-33' are equipped with valves 39 and 40, respectively,

and are selectively seatable on appropriate seats the pump and conduit 46 connected thereto leads,

to the bearings and moving parts of the engine.

Conduit 41 also connected to conduit 45 has afl bore substantially smaller than the bore of conduits 45 and 46, permitting only a. small amount of oil to pass through it. Conduit 41 is connected to a port in closure it of housing 3? and oil is thereby introduced into chamber 49. Chamber 49 communicates with chamber 58 formed in housing 31 by the aid of channel 55 whenever the valve 49 of piston member 38' is notacontactingtm seat 4|. When piston memhers .;3,8;and=38 are in their left-hand position, therconnectingqmember 42 is positioned in respectito chamber 50 as illustrated in Figure 4. essentialgthat the maximum width of the circular groove formed by the small diameter member. 42 is .less than the distance between 4| andJL-ofjthe cylinder bore in order to assure that, the,-;oil IS in casing 6 can never communicate-directly with the chamber 5|).

Qfl. Supplied by conduit 41 is continuously circulatddthroug'h chambers 49 and 5|! when pressure-exists in the reservoir in casing 6. and is returnedtosump 44 through a conduit 5| secured irr port; 52. It isressential that the outlet member 52 is. so dimensioned that under no condition the. freshj oilv supply furnished through pipe 47 canraise the oil. level materially above the line 53 in Figure 5. The oil level in chamber 50 is maintained at the same level as the surface 53 (Figure,- 5)- and when pistons 38-38 oscillate in the cylinder bore in housing 37, a given amount ofaoilgis. injected into the reservoir of casing 6 tdmaintain the :oil level at the desired height Shindicatedinfiigures 3 and 5.

gistons 3fle-38rare forced to the right by the air pressure acting on the oil in casing 6 and theyzare forced to the left when the oil pressure derived from pump 43 exceeds the pressure in casing or when the compressor is idling and the reservoir in the casing t is relieved to atmos- Dh,

A ss u m ing that the unloading valve (not shown) forjthe ,pump is, closed, piston 38 will be forced to;the,.,right because of the pressure developed thereby seating valve 39 on seat 4|, thus'preventing pressure fluid escaping through h uSing-B'L -When the requirements of tank It aresatisfied, the compressor inlet valve is closed, whereupon. the pressure is relieved on the oil supply 9. Oil now entering chamber 49 (Figure 41.;movespistons 38-387 to the left, causing valve 40 to seatonjvalveLseat 4| and the given quantity f,Q1'1 inthe space surrounding connecting member 42 and the cylinder bore is added to the lubricant supply Hi. In the event that the level of -theoil in the compressor reservoir 6 is higher than the overflow level 53 (Figure pistons 38-38, during the succeeding right-hand movement, withdraw an amount of oil which is returned to reservoir 44 through conduit 5|.

What I claim is:

1. A mechanism for replenishing the oil supply in an air compressor comprising a casing for the; compressor provided with an oil reservoir which is periodically subjected to variations in pressure; injector means to introduce oil into said casing; an oil source from which oil is supplied to said injector means; means to operate said injector means when the oil in the casing reservoir is subjected to variations in pressure to thereby inject oil into said casing reservoir; and means responsive to compressor pressure to prevent loss of pressure after each operation of said injector means.

2. A mechanism for replenishing the oil supply in...an air compressor comprising a casing for the compressor provided with a reservoir containing oil which is periodically subjected to variations in pressure; an oil injector; an oil source; means to conduct oil from said source to said injector; means to operate said injector when the oil in the casing reservoir is subjected to variations in. pressure to thereby inject oil into said casing reservoir; and means responsive to compressor pressure-to prevent loss of pressure after each operation of said injector means.

3. A mechanism iorreplenishing the oil supply.

in an air compressor comprising a casing for the compressor provided with a reservoir containing oil which is periodically subjected to variations'in pressure; an oil injector mechanism mounted on said casing; an oil source; means to conduct oil from said source to said injector mechanism;

means tooperatesaid injector mechanism when the oil in the casing reservoir is subjected to variations in pressurein order to transfer oil insaid injector to said casing reservoir; and means-to re: turn someuofuthe oil supplied: toisaid injector 1 r mechanism to said source. L 3

4. A mechanism for replenishing the oil supply in an air compressor comprising azcasing provided with an oil reservoir having oil therein which is alternately subjected to atmospheric and compressor pressure; an injector housing associated 'with said casing having a bore and an oil receiving chamber therein; an oil source; a pump to transfer oil from said source to said chamber; injector means in said bore movable by pressure derived from said pump to transfer oil from said chamber into said reservoir when the oil reservoir is subjected to atmospheric pressure; an a valve associated with said injector means responsive to compressor pressure to prevent loss of compressor pressure through said housing.

5. A mechanism for replenishing the oil sup-- ply in an air compressor comprising a compressor casing provided with a reservoir having oil therein which is periodically subjected to compressor pressure or'atmospheric pressure; a source of oil; an injectorv housing secured to said casing said housing provided with an oil receiving chamber; means to transfer oil from said source to said chamber; a reciprocable injector member in said housing to transfer oil from said injector housing chamber to said reservoir; means to move said injector member in one direction when the oil insaid reservoir is subjected to atmospheric pressure; and a valve on said injector member which is closed when said member has been moved by compressor pressure in the opposite direction to prevent the escape'of compressor pressure.

6. A mechanism for replenishing the oil supply in an air compressor comprising a compressor casing provided with an oil reservoir having oil therein which is alternately subjected to atmospheric or compressor pressure; a source of oil; an injector housing associated with said casing provided with a bore and an oil receiving chamber;

means to conduct oil from said source to said chamber; a reciprocable injector member in said bore; means to operate said injector member to transfer oil from said chamber into said reservoir when the reservoir oil is subjected to atmospheric pressure; and means responsive to compressor pressure to prevent loss of pressure from said casing through said bore when the oil in said reservoir is subjected to compressor pressure.

7. A mechanism for replenishing the oil supply in an air compressor comprising a casing provided with a reservoir having oil therein which is alternately subjected to atmospheric or compressor pressure; an injector housing associated with said casing having a bore and an oil receiving chamber therein; an oil source; a pump to transfer oil from said source to said chamber; an injector member in said bore movable by pressure derived from said pump to transfer oil from said chamber into said reservoir when the reservoir oil is subjected to atmospheric pressure and reversely movable by compressor pressure to transfer excess oil from said reservoir to said chamber; a valve associated with said injector member closable by compressor pressure to prevent loss of compressor pressure through said housing; and means to return the excess oil supplied to said housing to said oil supply.

8. A mechanism for replenishing the oil supply in an air compressor comprising a casing provided with a reservoir having oil therein which is subjected to atmospheric or compressor pressure; an injector housing associated with said casing having a bore and an oil receiving chamber therein; an oil source; a pump to transfer oil from said source to said chamber; means to operate an injector member in said injector housing when said reservoir oil is subjected to atmospheric pressure to transfer oil from said chamber to said reser voir; means responsive to compressor pressure to operate said injector member to transfer excess oil from said reservoir to said chamber; and a valve on said injector member closed by compressor pressure to prevent loss of compressor pressure.

9. A mechanism for replenishing the oil supply in an air compressor comprising a casing provided with a reservoir having oil therein which is subjected to variations in pressure; an injector housing associated with said casing having a bore and an oil receiving chamber therein; an injector member operable in said bore; an oil vessel disposed above said housing; means to enable oil to flow from said vessel to said chamber; a spring to move said pump member when the reservoir oil is subjected to variations in pressure to transfer oil from said chamber into said reservoir; and a valve on said injector member responsive to compressor pressure to reversely move said pump member and close said valve.

CYRIL B. FITES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 795,676 Ammen July 25, 1905 1,650,091 Nelson Nov. 22, 1927 2,178,100 Gygax Oct. 31, 1939 2,285,426 Freeman June 9, 1942 

